Three games in and the Dead Space series has got problems. And I'm not referring to the fact that protagonist Isaac Clarke has cleverly managed to crash-land on an inhospitable ice planet that may hold the horrible secret to the entire Necromorph space-zombie menace.

The problem is the Necromorph menace itself. Or rather, the fact that, after all this exposure in the Dead Space games, it isn't really that menacing any more. The resurrected space-dead are still pretty ghastly, perhaps, with their spider's legs, collapsed faces and that nasty ability to sprout tangles of gristle from the least likely of places, but we've been looking them straight in their oozing dead eyes for a couple of games now, and over time you can become immune to just about anything.

Example? Early on in the latest Dead Space 3 demo, I was wandering around another abandoned space hulk looking for another way to get past another locked door when a Slasher dropped down from the ceiling in front of me, accompanied by a sudden shriek of sound design. I should have leapt from my chair or watched in horror as my beard turned white and fell out, one hair at a time. Instead, I just took aim at a juddering limb and idly wondered how the thing managed to climb all those ladders with talons in place of hands.

Don't let student Necromorphs steal your Hobnobs.

Visceral Games have at least one decent solution to the problem of audience complacency, as it happens, but they waited until a fair proportion of the demo had passed before revealing it. For the first ten minutes, it was business as usual ' and business as usual is pretty much the kiss of death when it comes to the production of startles and shocks. I was wandering around an empty ship, collecting ammo and health packs, listening to audio logs left by a deceased crew, and besting the odd toggle puzzle, when I found a door that wouldn't respond to a smart blast of telekinesis. If the team were building up to a big fright, it had better be a belter.

Luckily, it was. It was a new kind of Necromorph called the Swarm Infector, and while it's a piddling thing on its own, scrabbling across the floor with tiny tendrils flying, it's capable of pulling an extremely unpleasant trick. Like the much larger Infector from the previous games, it can reanimate any nearby corpses, sending them spasming into epileptic life. They judder around for a few horrible seconds, then the gristle starts to warp outwards and ' presto ' you've got another Slasher on your hands.

It's standard Dead Space stuff, perhaps, but combining the Infector with the series' diminutive Swarmers has resulted in a genuinely unnerving combination. Once again, corpses can no longer be treated as mere set dressing, and there's something new to squash underfoot.

Elsewhere, if the team has to struggle a little harder in order to scare you, the consolation prize is that Dead Space 3 still looks like an atmospheric and fiercely competent action game. Isaac has clearly been having the futuristic equivalent of Hot Yoga sessions, as he's generally a little quicker on his feet this time around and can now combat-roll away from danger when things get bad. He's also joined by a brand new co-op partner, in the form of Sergeant John Carver, an EarthGov super-soldier and all-round grumpy hard nut whose family has been wiped out by the Necromorphs.

Slashers have a bone-extrusion to pick with you

Co-op play is of the drop-in, drop-out variety, and although it will open new paths through the levels and even unlock the odd additional side mission, it's entirely optional. Inevitably, it makes the whole thing even less scary than it already is at this point in the series. Down on the frozen surface of the ice planet Tau Volantis, however, there are suggestions that the developers haven't completely given up on creating an air of prickly tension. Snowstorms reduce visibility, while nearby science installations are covered with flapping cables and guide wires, encouraging us to waste precious ammo shooting at shadows.

Carver's presence has also enabled the design team to scale up the enemies, chucking the duo against a vast hairy spider known as the Snow Beast, and a huge out-of-control drill. The latter has a glowing core that has to be shot out using well-timed blasts of stasis while your partner keeps you safe from the crowd of Necromorph monsters and Unitologist soldiers now gunning after you as well. The developers have yet to reveal all of the game's new weapons and enemies, but with the head count steadily increasing in most battles, it wouldn't be entirely surprising if the firepower starts to escalate too.

If Dead Space 3 can't always keep you quaking in your spaceboots, it should at least keep you busy. That's not the ideal path for a survival horror franchise to take, but it's better than the alternative ' which is generally an accidental lunge towards painful self'parody.